Pneumatic relay system



June 26, 1962 R. w. COUFFER, JR, ETAL 3,040,766

PNEUMATIC RELAY SYSTEM Filed Feb. 9, 1959 2 Sheets-Sheet 1 Lye Elm-'5fioberf W Coal/1%? Jr Joseph M. A/gizzo June 26, 1962 R. w. COUFFER,JR., ETAL 3,040,766

PNEUMATIC RELAY SYSTEM Filed Feb. 9 1959 2 Sheets-Sheet 2 be Elm- 5foberf W flouff'er (/2? Joseph M. A/yino United States Patent 3,048,766PNEUMA'EEHC RELAY SYSTEM Robert W. Con er, 3:2, Oak Park, and Joseph M.Algino, Chicago, 113., assignors to The Dole Valve Company, MortonGrove, Iil., a corporation of Illinois Filed Feb. 9, 1959, Ser. No.792,085 1 Claim. (U. 137-102) This invention is directed generally topneumatic relay systems and the like and is more particularly directedto a pneumatic relay system particularly adapted to be used incontrolling the electric and pneumatic actuation of various mechanismssuch as might be found in a washing machine.

In recent years it has been found to be quite advantageous to controlthe operation of various component parts of washing machines, such asthe agitator mechanism, the shut off and/ or mixing valve, the cyclingmech-' anism, etc. pneumatically and to provide a central pneumaticrelay system coupled with a suitable timing mechanism to efifectactuation of each of these components.

It will be understood that such pneumatic systems require a pneumaticpump to feed pressurized air to the timing device or to the individualpneumatically controllable mechanisms and that a power source must beutilized to drive the air pump of the pneumatic system. In the past,such pneumatic pumps have generally been driven through separateelectric motors and gear reduction units or have been driven off themain washing machine motor itself constantly throughout the washingmachine cycle. The foregoing means for driving the pneumatic pump havenot proved entirely satisfactory, however, for the following reasons:Washing machine motors, as is well known in the art, are generallyone-third horsepower units, or less, and are frequently used to fullcapacity at various points in the cycle of operation of the washingmachine so that any additional load which the motor might be subjectedto, such as the load applied in operating a pneumatic pump, would tendto overload the motor and the machine would stop. For exemplarypurposes, it will be noted that the main motor might be used to fullcapacity in a situation wherein the machine cycle is stopped by theoperator and is again restarted during the rinse operation so that themotor must bring the tub full of water and clothes up to the spin speed.Furthermore, it would obviously not be economically practical tosubstantially increase the horsepower of the main washing machine motorsimply to power a pneumatic pump. In this same regard, it is obviouslynot economically practical to provide a separate electric motor and gearreduction unit for driving the pneumatic pump for a pneumatic relaysystem as has been done in the past.

Mindful of the foregoing and in an attempt to obviate thedisadvantageous features set forth above, applicant has devised apneumatic relay system including a pneumatic pump wherein the pump isdriven intermittently by the main washing machine motor but wherein themain motor is not utilized to operate the air pump during'thoseintervals when machine loads are applied to the motor.

In general applicants pneumatic relay system, which is hereinafter setforth with particularity, includes a pneumatic pump having areciprocably movable compressor diaphragm therein and having a reservoirassociated therewith which is associated with the main washing machinemotor in such a manner that the compressor diaphragm is arranged to bereciprocably driven by the motor. The pressure reservoir associated withthe pneumatic pump is communicable with a control valve which isoperable to selectively direct pressurized air to a main pneumatic lineleading to a pneumatic timer or similar ice control device. The controlvalve is arranged to close communication between the reservoirassociated withthe pneumatic pump and the main pneumatic line until thepressure within the reservoir has been built up to a predetermined levelby reciprocation of the diaphragm within the pneumatic pump and isthereafter operable to open communication between the reservoir and themain pneumatic line to direct pressurized air to the pneumatic timerwithin the washing machine from whence it is subsequently diverted toits point of utilization. In the embodiment of the invention illustratedin the drawings appended to this specification a pressure regulator isshown as being situated Within the main pneumatic line to maintain thepneumatic pressure in the line on the downstream side thereof at apreselected maximum.

The atmospheric inlet to the pneumatic pump has a check valve associatedtherewith which is operable to permit unidirectional air flow into thecompression chamber of the pump which, in turn, has an air operatedvalve as.- sociated therewith which. is effective to close communicationbetween the atmosphere and the compression chamber of the pneumaticpump. A second check valve is also seated within the pneumatic pumpwhich is effective to permit unidirectional air flow from thecompression chamber of the pump into the pressure reservoir. When thecheck valve at the inlet to the pump is closed, upward movement of thediaphragm within the pneumatic pump will effect compression of the airwithin the compression chamber to force the same through the secondmentioned check valve and into the reservoir but a vacuum will becreated within the compression chamber to thereby hold the diaphragm inits compression-stroke position to thereby inactivate the diaphragm thusreleasing the pneumatic pump load from the main washing machine motor.

The control valve which forms a part of the presen invention comprisesgenerally a valve body hawng a diaphragm chamber and a cylinder formedtherein in axial alignment with one another. A flexible diaphragm,extends across the interior of the diaphragm chamber to divide thediaphragm chamber into an air and a spring chamber on opposite sides ofthe diaphragm and is operably connected, through a motion translationmember, to a spool valve disposed within the cylinder. inder has aninlet and a pair of outlets spaced longitudinally along the cylinderwhich are each communicable with the interior thereof. The cylinderinlet is adapted to be connected to a source of pressurized air, such asthe pneumatic pump hereinbefore described, While'one of the cylinderoutlets is communicable with the interior of the air chamber on one sideof the diaphragm to urge the diaphragm and consequently the spool valvein a first direction. 'Spring means are disposed within the springchamber to bias the diaphragm in an opposite direction and to normallymaintain the spool valve in a position closing communication between thecylinder inlet and the second outlet from the cylinder, which isconnected to the main pneumatic line.

A small atmospheric bleed orifice is formed through the valve body whichis communicable with the interior of the spring chamber. the air chamberfrom the cylinder inlet, the increasing force of pressurized air withinthis chamber tends to compress the spring acting on the opposite side ofthe diaphragm and to move the diaphragm against the opposing biasingforce thereof. Movementof the diaphragm in this mannerwill, however,tend to compress the air within the spring chamber so that both theforce of the spring and the pressurized air within the spring chamberwill oppose the oppositely directed force of pressurized air within theair chamber. The volume of air The cyl-v As pressurized air is directedto FIGURE 1 is aview within the spring chamber will, of course, begradually reduced as air is bled from the chamber through theatmospheric bleed orifice but this-flow of air will be relatively smalldue tothe' size of the orifice so that a time lag or hysteresis effectis incorporated in the operation of the diaphragm.

During the interval when the diaphragm is thus beginning its downwardmovement within the diaphragm chamber the pneumatic pressure within theair chamher and the compressor reservoir will be constantly increasing.When the pneumatic pressure within the air chamber finally becomessuflicient to overcome the oppositely directed force of the pressurizedair and the spring within the spring chamber, the diaphragm will bemoved downwardly within the diaphragm chamber to effect movement of thespool valve to a position to open communication between the cylinderinlet and the second cylinder outlet to thereby communicate pressurizedair from the compressor reservoir to the main pneumatic line.

When pressurized air is directed to the main pneumatic line air isdirected to the air operated valve associated withthe inlet checkvalve'in the pneumatic pump and the inlet to the pneumatic'pump isclosed and the pneumatic pump is uncoupled from themotor in the mannerwhich has hereinbefore 'been described. Thus, the pneumatic pumpisinactivated until the pneumatic pressure within the main fluid line andthe compressor reservoir has been reduced sufficiently to the pointwherein the spring associated with the diaphragm will move the diaphragmand the spool valve associated therewith in a direction to vent the mainpneumatic line to the atmosphere and effect opening of the inlet to thepneumatic pump to initiate another pump operating cycle.

An electrical switch is also associated with the pneumatic relay systemto control the energization of various electrical components in thewashing machine such as,

for instance,-the pneumatic timer mechanism, and is so arranged that theswitch is closed to energize the various electrical components onlyduring those intervals when the pneumatic pump is inactivated and sothat upon activation of the pump by the main washing machine motor, theelectrical contacts in the switch are opened to deenergize theelectrical components associated therewith.

Accordingly, it is a principal object of the present invention toprovide a pneumatic relay system particularly adapted to control thepneumatic and electrical actuation of various components in a washingmachine.

A further object of the present invention is to provide a pneumaticrelay system having a pneumatic pump associated therewith which isintermittently driven by the main washing machine motor only during hoseintervals .when little or no machine load isapplied to the motor.

A still further object of the invention is to provide a control valveassociatedwith a pneumatic relay system of the type herein describedwhich is operable to close communication between the compressorreservoir associated with the pneumatic pump and the main pneumatic lineuntil a predetermined fluid pressure has been built up within thecompressor reservoir and to thereafter open communication therebetweenuntil the pneumatic pressure th ecompressor reservoir has been reducedto others inside'elevation, and stillothers in vertical sec- 7 FIGURE 2is a vertical sectional view through a control valve constructed inaccordance with the principles of the present invention and showing thediaphragms and spool valve therein in a first'position;

FIGURE 3 is a fragmental vertical sectional view of the control valveillustrated in FIGURE 2 but showing the diaphragms and spool valve in asecond position;

FIGURE 4 is a vertical sectional view through the check valve which isutilized in the illustrated embodiment of the present invention; and

FIGURE 5 is another vertical sectional view through the check valveillustrated in FIGURE 4 but taken on a plane perpendicular to that of-FIGURE 4.

In the embodiment of the invention illustrated in the drawings, there isshown diagrammatically a main washing machine motor 10 which is operatively associated with a pneumatic pump 11 to drive the same. The pneumaticpump includes generally a compressor 12 and a compressor reservoir 13.

A pneumatic control valve 14 is associated with the compressor reservoir13 and is adapted to controllably direct pressurized air from thecompressor reservoir 13 to a main pneumatic'line 15. The main pneumaticline 15 has a pressure regulator 16 associated therewith which isadapted to maintain a constant maximum pressure on the downstream sidethereof Within the pneumatic lines but which, it should be noted, is notan essential element in the pneumatic relay system which forms thesubject of the present invention. 7 A branch pneumatic line 17 leadsfrom the main pneumatic line, on the downstream side of the pressureregulator 16, to the compressor 12 to control the operation of thecompressor in a manner which will hereinafter be more fully described indetail.

The compressor 12 comprises generally a valve block 20 to which areservoir housing 21 is sealed by means of a gasket 22. The reservoirhousing 21 may be secured to the block 20 in any suitable manner. Aninlet port 23 is formed within the valve block in communication with theline 17 while an outlet port 24 is formed therein in communication withthe interior of the reservoir housing 21.

A compression chamber 25 is formed and defined by a recessed portion inthe bottom of the valve block 20 and by a flexible diaphragm 28 whichextends thereacross. Preferably the diaphragm 28 has an outer annularraised bead 29 which is seated in a mating groove 30 formed in the valveblock 20.

The diaphragm 28 may be made out of rubber or any one-of the knownsubstitutmtherefor and is provided with a reefiorced central portionwhich is formed with an annular disk 31 held on the underside thereof bymeans of a depending lip 32 of the diaphragm 28.

A base plate or cap 33 extends over the diaphragm member 28 and retainsthe marginal edge thereof seated against the valve block 20. The baseplate 33 includes a cup portion 34 and av hollow stem portion 35 whichreceives a reciprocable power shaft 36. An air vent 37 is provided inthe base plate 33 to keep the underside of the diaphragm 28 incommunication with the atmosphere to prevent pressure buildupintermediate the diaphragm 28 and the base plate or cap 33,

The power shaft 36 is operatively connected at its upper end to thediaphragm 28 and at its lower end to a yoke 38 within which is mounted apin 37a rotatab'ly supporting a cam follower wheel 39. An annular disk40 carried by the shaft 36 at its lower end portion provides a reactionmeans for a compression spring 41 which extends between the cap member33 and the annular disk 40.

The wheel or roller'39 rides on a cam 45 formed on the upper surface 46of a cam wheel 47. The cam wheel .47 is rotatably supported on an outputpower shaft 48 of the main washing machine motor 10 and is rotatablydriven thereby.

An outlet check valve 50. is seated within the outlet port 24 on anannular flange 51 formed integrally with the valve block 20 and ismaintained in seating engagement therewith by means of a cylindricalring 53 which frictionally engages the sidewall of the port 24. It willhere be noted that the outlet check valve 50* is, arranged to permitonly unidirectional flow from the compression chamber 25 to thereservoir 21. Similarly, an inlet check valve 55 is seated within anenlarged diameter portion 56 of a fluid inlet passageway 57 which isarranged to provide fluid communication between the inlet port 23 andthe compression chamber 25. It will further be noted that a flexiblediaphragm 58 has a peripheral bead 59 seated within an annular groove 60formed within the valve block 26 and that a valve member 61 is suitablycentrally secured to the diaphragm 58 in coaxial alignment with thecentral passageway in the inlet check valve 55 to control fluid flowtherethrough in a manner which will hereinafter become more fullyapparent. The diaphragm 58 is normally urged to the position illustratedin FIGURE 1 by a spring 58a and is moved in an opposite direction byfluid pressure as will hereafter be described.

The check valves 50 and 55 are alike and each includes a valve body 62formed of rubber or the like. The valve body 62 has a depending somewhatflattened hollow portion 63 which is generally of rectangularcross-section. Member 63 has an elongated passageway 64 therein incommunication with a central passageway 65 in direct alignmenttherewith. Disposed within the hollow portion 63 is a pin 66 whichextends lengthwise thereof and which is snugly retained at opposite endsby the end walls of the portion 63. The sidewalls of the portion 63 inconjunction with pin 66 form a valve to restrict the passage of airthrough the unit. Pin 66 has its opposite ends rounded as at 67 where itengages the opposite ends of passageway 64 and slightly stretches themember forming that passageway. Two depending tongues 63 extenddownwardly toward pin 66 and serve to properly locate pin 66.

Whenever the pressure around the outside of the elongated passagewaymember 63 is less than the air pressure at the inlet 70 of the checkvalve, the walls of the passageways 64 yieldably expand and spread apartto permit the movement of air past the pin 66 to the outlet '71 of thecheck valve. When, however, the pressure surrounding the elongatedpassageway portion 63 is greater than the air pressure at the inlet 70of the check valve, the greater air pressure on the exterior of thepassageway member 63 will collapse the walls 63 and prevent the passageof air past the pin 66.

It will thus become-apparent that the valve member or plunger which isconnected to the diaphragm 58 acts as a valve and is arranged to openand close the inlet 79 of the inlet check valve 55.

The operation of the pump is somewhat as follows: Assume, forillustrative purposes, that the cam wheel or roller 39 is resting on thecam Wheel 47 at the beginning of the cycle of operation. As the camwheel 47 is rotated, cam roller 39 will ride up onto the high portion ofthe cam which, in turn, will force shaft 36 upwardly against the actionof spring 41 and the diaphragm 28 will be moved upwardly intojuxtaposition with the uppermost portion of the compression chamber 25.The spring member 41 will act to return the roller39 to the levelillustrated in FIGURE 1 upon further rotational movement of the camwheel 47. Since the outlet check valve will not permit the passage ofair from the reservoir chamber to the compression chamber '25, a partialvacuum will be formed within the compression chamber causing the air onthe inlet side of check valve to expand the sidewalls of the check valveto open the air passageway into the compression chamber 25 and permitthe flow of air thereto from the atmosphere. When the power shaft 36 andthe diaphragm are again raised to their uppermost position by the cam45, the increased pressure of air caused by the piston action of theupwardly moving diaphragm on the outer walls of the inlet check valvewill be greater than the pressure on the inlet side of the valve 55, andthe inlet check valve 55 will close. on the upstroke of the diaphragmthe pressure at the inlet '70 of the outlet check valve 24 will begreater than the pressure surrounding the elongated passageway walls andthus air will pass through the valve from the compression chamber 25 tothe reservoir 21.

Upon closure of the inlet check valve 55 by the valve member 61associated with diaphragm 58, the diaphragm 28 will be renderedinoperative after moving through its compression stroke since a vacuumwill be created above the diaphragm so that the air pressure actingupwardly on the diaphragm and communicated to the underside of thediaphragm through the vent port 37 will be sufliciently great toovercome the opposing biasing force of spring member 41. The diaphragm28 will thus remain in its upper position so long as the inlet checkvalve 55 remains closed by valve member 61. Thus, even though the camwheel 47 is rotating, the diaphragm will not be moved and no additionalair will be forced into the accumulator chamber or reservoir 13.Accordingly, the load of driving the pneumatic pump 11 will be releasedfrom the main motor 10.

Referring now particularly to FIGURES 2 and 3 of the drawings, thecontrol valve 14 is shown as comp-rising generally -a valve body 80having a diaphragm chamber 81 and a cylinder 82 formed therein incoaxial alignment with one another. An inlet nipple 83 and a pair ofoutlet nipples 84 and 85 are formed integrally with the valve body 80and have passages formed axially therein which are communicable with theinterior of the cylinder 82. The inlet nipple 83 is adapted to beconnected to a suitable hose or tube 86 which is, in turn, suitablyconnected to the reservoir 13 to communicate pressurized air from theinterior of the reservoir to the cylinder 82. Another connecting nipple87 is formed integrally with the valve body 80 and has a passage formedaxially therein which opens to the interior of the diaphragm chamber 81and which is adapted to be connected to a suitable hose or tube 89which, in turn, is connected at its opposite end to the nipple 84 andwhich is adapted to communicate air from the interior of the cylinder 82to the diaphragm chamber 81.

An annular groove 90 is formed about the side wall of the diaphragmchamber 81 which is adapted to receive and form a seat for a thickenedperipheral head 91 of a flexible annular diaphragm 92. The flexibleannular diaphragm 92 thus extends entirely across the interior of thediaphragm chamber 81 and divides the chamber into an air chamber 92 anda spring chamber 94. In this regard, it will be noted that theconnecting nipple 87 is so positioned that the axial passage thereinopens to the air chamber 93.

It will also be observed that a stiffening plate 95 is molded within thediaphragm 92 but that the plate has a diameter somewhat less than thediameter of the chamber 31.

Coaxial apertures 96 and 97 are formed within the valve body 80 withinwhich a motion translation rod 98 is disposed. An annular groove 99 isformed Within the valve body 30 about the aperture 96 and is adapted toform a seat for an O-ring 100 which is disposed therein to maintain afluid tight seal between the motion translation rod 98 and the wallportion of the valve body 80 defining the aperture 96.

It will be understood that the motion translation rod 98 is suitablyaffixed to the diaphragm 92 so that it will move colinearly therewithand that the upper end portion of the rod 98 is arranged to abut theupper wall portion of the valve body 80 defining the diaphragm chamber81 to limit theupward movement of the diaphragm 92.

A pair of valve members 102 and 103 are afiixed to the motiontranslation rod 98 in spaced relation with However,

respect to one another and are disposed within the cylinder 82 andslidably engage the inner wall of the cylindert82.

It will further be understood that the valve members 102 and 103 form,in conjunction with that portion of the motion translation rod 98extending intermediate the valve members, a spool valve 105 which ismovable within the cylinder 82 to selectively communicate pressurizedair from the inlet 83 to the outlets 84 and 85.

Thus, when the spool valve 105 is in the positoin illustrated in FIGURE2, pressurized air is communicated from the compressor reservoir 13 tothe outlet84 and then from the cylinder 02, to the air chamber 93 on theupper surface of the diaphragm 92. It will be noted that when the spoolvalve is in this position, no pressurized air is communicated from thecompressor reservoir 13 to the outlet 85 due to the positioning of thevalve memher- 103 intermediate the inlet 83 and the outlet 85, and themain pneumatic line is, as a result, vented to the atmosphere through avent port 107 which is suitably formed within the valve body 80 at thelower end of the cylinder 82. p i

.A spring member 106 is disposed within the spring chamber 94intermediate a wall portion of the valve body 80 and the diaphragm 92which is efiective to oppose the pneumatic force within the air chamber93 and urge the diaphragm 92 upwardly within the diaphragm chamber 81. Avent port 108is also formed through thewall of the valve body 80 tocommunicate the interior of the spring chamber 94 with the atmospherewhich is operable to eliect hysteretic movement of the diaphragm in amanner which will hereinafter be described in more detail.

An electrical switch 110 is disposed at the lower end of the cylinder 82and comprises generally a mounting bracket 111 which is suitably aflixedto the valve body 80, and a pair of electrical contacts 112 and 113which are disposed in spaced relation from one another and which aresuitably aifixed to the bracket 111. It will be noted that the contact112 is engaged by the protruding outer end portion of the motiontranslation rod 98 so that reciprocable movement of the rod 98 will actto move the contact 112 into and out of engagement with the contact 113to thereby open and close an electrical energizing circuit through theswitch 110.

It will here be understood that the bleed passage 108 which functions tocommunicate the interior of the spring chamber 94 with the atmosphere,is made extremely small 'so that-a relatively small rate of air flow ispermittedtto pass therethrough. In this manner, while the constantlyincreasing'force of pressurized air within the air chamber 93 might besufiicientto compress the spring member 106 the diaphragm will not movedownwardly at once, since the pneumatic pressure within the springchamber 94 will also be resisting downward movement of the diaphragm 92.Gradually, air will be forced out of the spring chamber 94 through thevent port 108, but by this time the pneumatic pressure within air.chamber 93 and reservoir 13 will be quite large. Thereafter, uponmovement of the diaphragm 92 downwardly within the diaphragm chamber 81,the spool valve 105 willbe moved from the position illustrated in FIGURE2 to the position i illustrated in FIGURE 3-to thereby opencommunication between the inlet 83 and each of the outlets 84' and 85.It will be noted that when the valve member 103 has been moved to theposition illustrated in FIGURE 3, to

openrcommunication between the inlet 83 and the outlet 85, communicationbetween the vent port 107 and outlet 85 will be closed. V 7

Conversely, even when the pneumatic pressure within the reservoir 13,the main pneumatic line 15, and the air chamber 93 has been reduced to apoint below that of the force of spring member 106 tending to urge thediaphragm 102 upwardly within the chamber 81, the'diaphragrn. 92 willnot immediately move upwardly a substantial amount since a partialvacuum will be created within the spring chamber 94 due to therelatively small rate of air flow through the orifice 108.

In this manner, a time delay feature or hysteresis effect isincorporated in the pneumatic relay system so that a relatively highpneumatic pressure will be built up within the reservoir 13 before theinterior thereof is communicated with the main pneumatic line 15, andthe compressor reservoir 13 will be maintained in communication with thepneumatic line 15 until a relatively low pneumatic pressure has beenreached within the reservoir 13.

In general, the operation of the entire pneumatic relay system will besomewhat as follows: Assuming that the washing machine motor 10 has justbeen started and the pneumatic pressure within the reservoir 13 isrelatively low, rotatable movement of the cam wheel 47 will effectreciprocable movement of the power shaft 36 to operate the compressor 12and to thereby force compressed air into the reservior 13. The variousparts of the control valve 14 will be in the position illustrated inFIGURE 2 and the pressurized air within the compressor reservoir 13 willbe communicated through the cylinder 82, and the outlet 84 to the airchamber 93 on the upper surface of the diaphragm 92. When the pneumaticforce within the air chamber 93 tending to urge the diaphragm 92downwardly within the air chamber 81 exceeds the opposing biasing forceof spring member 106, the diaphragm will begin to move downwardly withinchamber 81 but such downward movement will soon be slowed due to the airpressure buildup within the spring chamber 94. The pneumatic pressureWithin chamber 94 will gradually be reduced as air seeps slowlytherefrom through the bleed orifice 108, but during that interval thepneumatic pressure within compressor reservoir 13 an air chamber 93 willbe constantly increasing. Finally, the diaphragm 92 will be moveddownwardly to the position illustrated in FIGURE 3 due to thedifferential forces acting on opposite sides of the diaphragm 92 and theoutlet 85 and the main pneumatic line 15 will then be communicated withthe interior of the compressor reservoir 13. Thus, pressurized air willflow from the reservoir 13 to the main pneumatic line 15 from whencepressurized air will be bled from time to time.

When the spool valve 105 has been moved to the position illustrated inFIGURE 3 to open communication between the interior of the compressorreservoir 13 and the main pneumatic line 15, pressurized air on thedownstream side of the pressure regulator 16 will be communicated to theunderside of the diaphragm 58 to move the diaphragm and the valve member61 associated therewith into juxtaposition with the inlet check valve 55to effect closure of the inlet check valve and to thereby maintain thediaphragm 28 and the power shaft 36 associated therewith intthe raisedor compression stroke position to thereby release the pneumatic pumpload from the main washing machine motor 10.

It will further be apparent that upon movement of the motion translationrod 98, downwardly within the valve body 30, the movable electricalcontact 112 of switch 110 will be moved into engagement with the contact113 to thereby close an electrical energizing circuit to an electricallyoperated device connected therewith which, for illustrative purposes,may comprise an electrically operated pneumatic timer As hereinbeforedescribed, the diaphragm 92 will not begin to move upwardly within thechamber 81 immediately upon the reduction of the pneumatic pressure inthe chamber 93 below that of the opposing biasing force of spring member106 since a partial vacuum will be created in spring chamber 94. Thediaphragm 92 will, however, gradually begin to move upwardly withinchamber 81 as pressure in chamber 93 is reduced until the spool valvehas again been returned to the position illustrated in FIGURE 2. Whenthe spool valve 105 has been returned to this latter position, the mainpneumatic line 15 will be communicated with the atmosphere through the 9vent port 197 so that the diaphragm 58 will again be re turned to theposition illustrated in FIGURE 1 and the pneumatic pump load will againbe impressed on the main washing machine motor 1% It Will herein beunderstood that in general the pneumatic pressure Within the compressorreservoir 13 will be built up to such a point that operating pressure isachieved and the pneumatic pump load is released from themain Washingmachine motor before the tub filling cycle of the washing machine hasbeen completed so that the pneumatic pump load will be released from themain motor 10 before any substantial machine load is applied to themotor.

It will also be noted that in general the build up of pressurized airWithin the compressor reservoir 13 at the beginning of the Washingmachine cycle will be sufiicient to supply pressurized air to thevarious pneumatically operated components of the Washing machinethroughout the entire cycle of the machine so that the pump 11 need notagain be operated during the Washing machine cycle.

It Will further be understood that this embodiment of the invention hasbeen used for illustrative purposes only and that applicants pneumaticrelay system may find varied uses in devices other than Washingmachines, and that various modifications and variations in the presentinvention may be efiected Without departing from the sprit and scope ofthe novel concepts thereof.

We claim as our invention:

A pneumatic control valve comprising a valve body having a diaphragmchamber and a cylinder formed therein, an inlet adapted to be connectedto a source of pressurized air and a pair of outlets opening to saidcylinders, a diaphragm extending across said chamber and peripherallysealed to a wall thereof forming an air chamber and a spring chamber onopposite sides thereof, I

spring means Within said springchamber biasing said diaphragm in onedirection, means communicating pressurized air from one of said outletsto said air chamber, a motion translation member connected to saiddiaphragm slidably mounted Within said valve body and extending intosaid cylinder, a valve associated With said motion translation memberand disposed Within said cylinder operable to selectively communicatepressurized air from said inlet to the other of said outlets, anatmospheric bleed orifice formed Within said valve body opening to saidspring chamber and effective to permit a restricted flow of airtherethrough such as to provide a time delay action for said diaphragmin response to variations in the pressure of air from said source ofpressurized air appliedto the diaphragm through said one outlet, and avent port opening to said cylinder and positioned to communicate withthe other of said outlets when said valve is disposed to preventcommunication of pressurized air from said inlet to the other of saidoutlets and to be closed from said other of said outlets by said valvewhen said valve affords communication of pressurized air from said inletto said other of said outlets.

References Cited in the file of this patent UNITED STATES PATENTSMueller et al. Dec. 31,

